Yes it would condiderably be faster. All though you only get 10k rpm hard drives in raid because 15000 rpm are scsi hard drives and you need an scsi pci controller card, because your mobo most likely wont have the connection. However you can setup 10,000's in a few differnt raid configurtions. You could even just setup 1 hard drive in raid and your other hard drive on ide and be fine too.
P4 2.26 ghz, Intel d850emv2 mobo, 768mb of pc800, sony 4x dvd-rw, teac burner, nvidia ti4600 graphics, enermax 330watt ps
4 silent uv fans, cold cathodes in full tower antec case, round ide cables
SOny vaio 2.66 ht ghz modded into raidmax case with green cold cathodes.
P4 2.8ghz HT, 512mb ddr, Intel KD865gbfl, onboard video, raidmax case, blue cathodes, round ide, loomed wires, 4x dvd burner, wd sata 80gb hard drive
Intel d865perl, 2.8ghz northwood, antec sonata, wd caviar 20gb, Corsair 512mbx1 for now. 380watt psu, ati 9600, dvdrom cdrw floppy in black too match case